This article is from the Calendars FAQ, by Claus Tondering firstname.lastname@example.org with numerous contributions by others.
At a meeting in Aleppo, Syria (5-10 March 1997), organised by the
World Council of Churches and the Middle East Council of Churches,
representatives of several churches and Christian world communions
suggested that the discrepancies between Easter calculations in the
Western and the Eastern churches could be resolved by adopting
astronomically accurate calculations of the vernal equinox and the
full moon, instead of using the algorithm presented in section 2.12.6.
The meridian of Jerusalem should be used for the astronomical
The new method for calculating Easter should have taken effect from
the year 2001. In that year the Julian and Gregorian Easter dates
coincided (on 15 April Gregorian/2 April Julian), and it would
therefore be a reasonable starting point for the new system.
However, the Eastern churches (especially the Russian Orthodox Church)
are reluctant to change, having already experienced a schism in the
calendar question. So nothing will happen in the near future.
If the new system were introduced, churches using the Gregorian
calendar will hardly notice the change. Only once during the period
2001-2025 would these churches note a difference: In 2019 the
Gregorian method gives an Easter date of 21 April, but the proposed
new method gives 24 March.
Note that the new method makes an Easter date of 21 March possible.
This date was not possible under the Julian or Gregorian algorithms.
(Under the new method, Easter will fall on 21 March in the year 2877.
You're all invited to my house on that date!)